My younger sister is on EBF and complains that she can't produce enough milk and it dries up. What could be the reason? The baby is 4 weeks 4 days
The dynamics of breast milk production is such that milk is produced by virtue of the stimulating effect of the child's suckling on its mother's nipples triggering a "letdown reflex" which delivers breast milk produced "de novo" [a new] directly to the breast ducts and into the baby's mouth [contrary to the popular belief that the bulk of breast milk is "stored" in the breast].

Kindly advice your sister on the need to relax and not to worry as it would negatively affect breast milk production. She needs to eat well and drink lots of water.

Breastfeeding is demand and supply. The more she puts the baby to breast, the more the milk flows.